During the 1970's fuel costs sharply increased. In addition, air traffic delays and airport congestion steadily grew worse. As a result, a manual navigational system for local flow traffic management was introduced in 1976. The system utilized fuel conservative profile descents which reduced low altitute flying times. Subsequently, the system was automated.
The automated system currently being utilized is a time-based metering system. Under this automated system, each arriving aircraft is assigned by the Air Traffic Controllers (ATC) a computer-calculated time to cross a metering fix (M*F) based on the airport's acceptance rate (see FIGS. 2 and 3). These metering fixes are usually located 25 minutes from the airport and a computer calculates the arrival time of an aircraft based on the time to cross the metering fix. The assigned metering fix times are displayed to the ATC. The ATC continuously check these times to determine if the acceptance rate of the airport will be exceeded. If the ATC detects that the airport acceptance rate will be exceeded, the aircraft may be delayed at the metering fix which is located in high altitude enroute airspace. As a result, fuel inefficient low-altitude delay maneuvers, and air traffic congestion in the immediate vicinity of the airport have been significantly reduced.
A Flight Management System (FMS) is presently available which is an extension of the area navigation (RNAV) capability originally certified for aircraft in 1971. It performs the basic RNAV functions of waypoint navigation and coupled guidance as well as tuning of the aircraft's VOR/DME receivers (Variable Omnidirectional Range/Distance Measuring Equipment), the automatic selection of VORTAC (collocated VOR and DME Facilities) stations, and the mixing of inertial, radio, heading and air data sensor inputs to provide optimal navigation accuracy and automatic control of engine parameters for all phases of flight. The system is comprised of a computer, a CRT control and display unit (CDU), and a CRT map display. This system merely informs the pilot of the aforementioned flight data for any given flight condition.
Accordingly, it is a general object of the present invention to provide an improved Flight Management System.
It is another object of the present invention to provide an improved Flight Management System which includes time-based control of an aircraft during cruise.
It is a further object of the present invention to provide an improved Flight Management System which includes time-based control of an aircraft during cruise which is capable of delivering an aircraft to a particular point in space at a required arrival time.